Please take caution if you go googling for OI - as always, medical images can be upsetting.

Taken from Wikipedia: Osteogenesis imperfecta (OI), also known as brittle bone disease, is a group of genetic disorders that mainly affect the bones. It results in bones that break easily. The severity may be mild to severe. Other symptoms may include a blue tinge to the whites of the eye, short height, loose joints, hearing loss, breathing problems, and problems with the teeth. Complications may include cervical artery dissection and aortic dissection.

Check out this neat visual... thing!

Source

For lions, this would be a lethal mutation - obviously! While there are multiple types of OI (at least nine), two are listed as lethal on the wikipedia but one is lethal during pregnancy, soooo...

Here is an idea for the lethal here, yoinked straight from the wikipedia.
Type II: Collagen is not of a sufficient quality or quantity.
Most cases die within the first year of life due to respiratory failure or intracerebral hemorrhage
Severe respiratory problems due to underdeveloped lungs
Severe bone deformity and small stature
Type II can be further subclassified into groups A, B, and C, which are distinguished by radiographic evaluation of the long bones and ribs. Type IIA demonstrates broad and short long bones with broad and beaded ribs. Type IIB demonstrates broad and short long bones with thin ribs that have little or no beading. Type IIC demonstrates thin and longer long bones with thin and beaded ribs.

But wait, I here you say, isn't this a human only thing?? Nope, again from the wiki!
In dogs, OI is an autosomal-recessive condition. In Golden Retrievers, it is caused by a mutation in the COL1A1, and in Beagles, the COL1A2. A separate mutation in the SERPINH1 gene has been found to cause the condition in Dachshunds.Several mouse models of OI have been described, whereby the abnormal gait 2 (AGA2) mouse line exhibits severe skeletal and cardio-pulmonary phenotypes due to a carboxy-terminus mutation in the COL1A1 gene in the mouse.

Appears: At birth
Affects Gameplay?: Yes, cub dies at 5 months (or earlier, I couldn't decide)
Lethal?: Yes

can i get uh....................... BONELESS CUB?

MUTATION SUGGESTIONS:
Spina Bifida [lethal] | Club foot | [YOU ARE HERE]
EYE SUGGESTIONS
Fruits for the Eyes | Assorted Eyes | Assorted Eyes: Part 2
MARKING SUGGESTIONS
November and Gem Markings | February and Gem Markings
Rosette Recolours | Giraffe and Inverted Giraffe
BASE SUGGESTIONS
Cake's Realistics | Cake's Semi-Realistics
Cake's Unrealistics | Cake's Combos
GENERAL SUGGESTIONS
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